Utility companies, home automation providers, industrial automation providers, scientific and environmental application providers, and other resource providers may communicate with low powered endpoints via parent devices operating on a time-slotted channel hopping (TSCH) network, such as that defined by IEEE 802.15.4. Parent devices (e.g., electric meters, routers) are connected and communicate with each other and with the resource provider via a TSCH network, which is referred to herein as the primary network or the primary TSCH network (PN-TSCH network). Parent devices are also referred to herein as parent nodes or TSCH nodes. Parent nodes on the primary TSCH network periodically switch channel frequencies according to a channel hopping protocol.
Low-energy (LE) devices are used to monitor and/or manage consumption of resources (e.g., electricity, heat, water, other utilities, as well as other types of resources). LE devices (also referred to as LE nodes, LE endpoints, LE endpoint nodes) include, for example, battery powered devices, energy harvesting devices, and vampire tapping devices. In some aspects, LE devices can be Internet-Of-Things (IoT) enabled devices that can be used in smart power grid and smart home technologies. Low energy devices are utilized as endpoints in TSCH networks and communicate messages with A/C powered parent nodes. LE endpoints utilize a second, low energy hopping pattern in a secondary TSCH network. The secondary TSCH network utilized by the LE endpoints uses a channel hopping protocol in which channel frequencies switch at a much slower rate than the primary TSCH network used by the parent devices. The secondary TSCH network is referred to herein as a LE-TSCH network. To save on power consumption and conserve battery life, the LE-TSCH network allows LE devices to enter a sleep state (i.e. turning off or placing in a low power mode higher powered electronics such as oscillators). Upon an LE device waking from sleep, the connected parent device initiates a Receiver Initiated Transmit communication to maintain clock synchronization based on clock drift. As part of a response to the RIT communication from the parent, the connected LE device may transmit check-in messages. Upon receiving the check-in message, the connected parent device may assert that downstream messages frames are pending for the LE device.
In some instances, multiple LE devices may be connected to a parent device on the TSCH network. Parent devices may need to broadcast transmissions to all connected LE devices. Multiple LE devices connected to the parent device may operate on different wake/sleep cycles and wake up from sleep states at different times. Because LE devices may wake up and transmit check-in messages and engage in Receiver Initiated Transport communication at different times with the parent devices, parent devices may need to serially repeat broadcast packets to each LE device as it checks in. As such, there is a need for a mechanism that optimizes broadcast transmissions from parent devices to connected LE devices.